The 'most probable number' (MPN) method is used in water quality assessment to detect:
- A Coliform organisms as an indicator of fecal contamination ✓
- B Total dissolved solids
- C Fluoride concentration
- D Dissolved oxygen levels
Correct answer: A. Coliform organisms as an indicator of fecal contamination
Explanation
The MPN method is a statistical estimate of coliform density in water, expressed as number of coliforms per 100 mL. Coliforms (particularly thermotolerant/fecal coliforms or E. coli) serve as indicator organisms for fecal contamination. WHO guidelines require zero E. coli per 100 mL in treated piped drinking water. MPN is used when membrane filtration is not feasible.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.